Embodiments of the inventive concept described herein relate to an apparatus for modulating build-up regions of photon beams by using a magnetic field and a beam spoiler, a radiotherapy apparatus based on photon beams including the same, and a method for modulating build-up regions of a photon beam by using a magnetic field and a beam spoiler, and more particularly, to an apparatus for modulating build-up regions, by which a depth dose is modulated in build-up regions of photon beams, a radiotherapy apparatus including the same, and a method for modulating build-up regions of photon beams.
A radiotherapy apparatus is a medical instrument that uses radioactive rays in treatment of diseases, and is widely used to delay, stop, or destruct growth of a malicious tumor tissue such as a cancer by using X-rays, photons, and charged radioactive rays, such as electron beams.
Meanwhile, when an excessive amount of radioactive rays having high energy are delivered to normal tissues or organs of a human body, DNA molecules are ionized and damaged, causing a mutation or killing cells so that the mutation caused due to the DNA damage may cause a genetic defect and may cause a cancer. Accordingly, when normal tissues and a tumor are close to each other, the radiotherapy dose often is not sufficiently irradiated due to a side-effect of the radioactive rays.
Accordingly, during the radiotherapy, the amount of radioactive rays and the disposition of the radioactive rays have to be adjusted such that a tumor that is to be destructed receives a sufficient amount of radioactive rays and a damage to normal tissues that surrounds the tumor is minimized.